A variety of structures, including cylindrically-shaped structures such as drums, have heat conductive walls to which insulation may be applied to the exterior, e.g., the weather side, of the cylinder. For example, a drum dryer for use in making bituminous concrete asphalt may have a heat loss reduction insulation cover. Thus, in U.S. Pat. No. 4,932,863 there is disclosed an insulation jacket for such a dryer. The jacket is wrapped around the outer peripheral surface of the drum dryer wall. The jacket can have an aluminum sheath with ceramic fiber being bonded to the sheath. The jacket is secured by bands of strapping wrapped around the jacket.
It would be desirable to provide such an insulation structure that could have not only snug fit on installation, but which would also make available ease of adjustment of fit in service. It would also be desirable to have an insulation jacket which takes into consideration ready repair, such as ease of disassembly as well as assembly, without deleterious loss of insulation quality after repair.